Предмет: Алгебра, автор: dianazavaryxina

Решить систему уравнений
{2x+y=20
{x-3y=-1

Ответы

Автор ответа: v127127v
1

Ответ: (\frac{59}{7};\frac{22}{7})

Объяснение:

2x+y=20    y=20-2x          y=20-2x          y=20-2x   y=20-2x  y=20-2*\frac{59}{7}   y=\frac{22}{7}

x-3y=-1      x-3(20-2x)=-1   x-60+6x+1=0   7x=59      x=\frac{59}{7}        x=\frac{59}{7}             x=\frac{59}{7}

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